Within GNS Narrativist play, a GM technique of
bringing NPC activities closer to the player-characters and to
introduce multiple responses among NPC and player-character actions.
Coined by Ron Edwards in the "Sex & Sorcery" supplement for
Sorcerer.

Wheedler

A term coined by John Kim on The Forge and prior discussion.
This is one of two types of power gamers, the other being a
"rules-lawyer". A wheedler gets his way by directly influencing
the GM and other players -- often by packaging personal power
with what the GM wants.
References:
Conflict Resolution and Gamism

Whiff Factor

The effect of a high failure-rate for a given Resolution mechanic,
especially when the rate does not accord with the character's
expected competence.

Wimpiness

Within GNS Gamist play, a dysfunctional form
of Gamism characterized by poor sportsmanship -- i.e. the
unwillingness to accept a loss.